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For the 12-month period ending 30th June 2007
Another drier than average month in rainfall deficient areas
With the notable exceptions of Gippsland and southeast Queensland,
June rainfall was mainly below to very much below average in the
rainfall deficient areas of southwest WA, southern and southeastern
Australia. Heavy to flood rains removed rainfall deficits in Gippsland,
while above to very much above average falls provided some relief in southeast
Queensland.
For the 12-month period from July 2006 to
June 2007, there were serious to severe
rainfall deficiencies over southern and eastern Australia in an
arc extending across southeastern SA, southwest, south-central
and northeast Victoria, and the tablelands and western slopes in
southeastern NSW. A large part of southeast Queensland was also
affected, as were northern and eastern Tasmania, and WA west of a
line from Dampier in the north to Bremer Bay in the south.
Record low falls for this particular 12-month period were recorded
near Albury-Wodonga, around Melbourne, in parts of northern Tasmania,
in the far southeast of SA and along WA’s west coast between Shark
Bay and Geraldton. Deficiencies are less extensive than they were for
the twelve months to May, mostly because June 2006 was much drier than
June 2007.
The worst of the long-term deficiencies are likely to remain for some time. For
them to be removed by the end of September, for example, falls over the
next three months would need to be in the highest 10% of the historical
record in some areas, especially in Victoria and WA.
The deficiencies discussed above have occurred against a backdrop of
multi-year rainfall deficits that have severely stressed water supplies
in the east and southwest of the country.
An important consideration in the recovery from drought is the different
rate at which systems respond to rainfall deficiencies. At the current
time, many catchments in eastern Australia are excessively dry from a
very protracted period of below average rainfall and above average
temperatures. This means that it will take above average rainfall just
to produce average runoff, and very considerable rainfall to make a
material difference to water storages.
Rainfall
deficiency maps for standard periods out to three years are
available.
Note: The terms used to describe rainfall in these
Drought Statements have the following meanings -
Serious deficiency
- rainfalls in the lowest 10% of historical totals,
but not in the lowest 5%
Severe deficiency
- rainfalls in the lowest 5% of historical totals
Lowest on record
- lowest since at least 1900 when the data analysed begin
Very much below average
- rainfalls in the lowest 10% of historical totals
Below average
- rainfalls in the lowest 30% of historical totals,
but not in the lowest 10%
Average
- rainfalls in the middle 40% of historical totals
Above average
- rainfalls in the highest 30% of historical totals,
but not in the highest 10%
Very much above average
- rainfalls in the highest 10% of historical totals
For more information regarding this rainfall
deficiencies statement, please contact the following
climate meteorologists in the National Climate Centre:
Grant Beard on (03) 9669 4527
David Jones on (03) 9669 4085
External Sites Relating to Drought
The Bureau of Meteorology does not make formal drought declarations
as these are done by either the relevant State Governments or by the
Australian Government. The Australian Government Program is called
Exceptional Circumstances
and it is administered by the Federal Department of Agriculture,
Fisheries and Forestry (DAFF). General information about Australian
Government drought assistance is available at
http://www.daff.gov.au/droughtassist.
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